This application claims the priority of German patent document 10 2009 040 735.9, filed Sep. 9, 2009, the disclosure(s) of which is (are) expressly incorporated by reference herein.
The invention relates to a side wall structure for a motor vehicle.
Side walls for motor vehicles usually comprise an inside shell made of steel plate and an outside covering connected to the inside shell. In order to simplify joining of the outside covering to the inside shell, the outside covering is itself usually constructed of steel. This permits a one-sided joining from the direction of the passenger compartment (for example, by beam welding). However, outside covering parts made of steel have the disadvantage of being very heavy. Previous attempts to provide an outside covering made of lighter materials also disadvantageously led to complex joining sequences and the necessity of using a plurality of connection elements.
It is therefore an object of the present invention to provide a vehicle side wall with reduced weight, and simultaneously a simple joining of the side wall is made possible.
This and other objects and advantages are achieved by the motor vehicle side wall according to the invention, which comprises an inside shell made of steel plate and an outside covering connected with the latter, particularly welded to the latter. The outside covering comprises an inside panel made of a steel alloy and an outside panel. By constructing the inside panel of steel, it becomes possible to maintain the previously customary joining sequence when connecting the outside covering with the inside shell. As a result, no complex changes in the manufacturing process will be necessary for using the side wall according to the invention. At the same time, the weight is reduced by constructing the outside panel of a material that has a lower weight than steel.
The outside panel is preferably glued together with the inside panel. By means of the adhesive layer, an electrochemical insulation is ensured in addition to a good hold between the panels. No contact corrosion problems will therefore occur between the aluminum sheet and the steel plate.
In order to provide the outside covering with particularly good strength, the outside panel is, in addition, preferably connected with the inside panel by way of at least one mechanical joining device. In an especially preferred embodiment, this is a solid punch rivet.
In a further embodiment of the invention, the outside covering part is welded to the inside shell by a one-sided welding process. In this case, the welding access preferably takes place from the side of the inside panel—thus from the side of the passenger compartment of the vehicle body. As a result, the usual joining sequence for the linking of side walls to body shells is maintained, so that a side wall constructed in this manner can be integrated particularly easily in existing production lines.
In a further embodiment of the invention, a B-column of the side wall is formed exclusively by the outside covering. The inside steel panel of the outside covering provides the B-column with sufficient strength, so that a further support by the inside shell of the side wall is unnecessary, thereby further reducing weight.
In preferred embodiments, the outside panel consists of an aluminum base alloy or a plastic material, both of which are particularly advantageous from the light-weight construction angle.
Other objects, advantages and novel features of the present invention will become apparent from the following detailed description of the invention when considered in conjunction with the accompanying drawings.